The Science of Building Muscle (Part 1)

For the majority of people training with weight seems like a fairly simple and easy-to-learn practice since everybody knows we need to lift weights, rest for a certain time then lift some more. Over time you will progress by continually improving your physical performance and the muscle tissue will gradually develop by increasing in both strength and size. However, in reality, things often don’t go as planned as the theory may suggest.

The relation between size and strength

Many bodybuilders have the notion that increasing one’s strength doesn’t necessarily relate to gaining new muscle tissue. You may have heard lots of times that bodybuilders are no match to powerlifters in terms of strength. However, this is a major misconception.

Let’s put out a theory: people who are strong tend to possess superior body mechanics in comparison to weak people. What we mean is superior joint lengths and connective tissue factors, including attachment placing, as well as greater ligament and tendon strength. People who are naturally strong have a greater amount of type II muscle fibers and a nervous system which is a lot more effective.

This is a subject to manipulation, however. You can train muscles to get stronger but you can’t train them to become bigger. Factors like the rep range used and workout session frequency play a big part. If a certain muscle becomes stronger and it is trained within a rep range best suited to eliciting optimal muscle gains, then it will start growing in size.

Numerous studies have proven repeatedly that muscle strength and muscle mass are directly related. In order to make this clearer, it very helpful to examine what happens inside the muscles when they are being trained. Muscle biopsies done on professional bodybuilders have shown that it was the individual muscle fiber size that was the greatest cause of the abnormally increased muscle size, instead of the number of muscle fibers inside the muscle.

Even though some studies have produced evidence that putting the muscle under extreme conditions might result in slight increases in the number of fibers, a process known as hyperplasia, the mechanism which is responsible for increasing muscle size is called hypertrophy, which is the increase in the size of the already existing muscle fibers.

It’s also worth mentioning that the contractile mechanism makes up approximately 80 percent of the muscle fiber volume. The rest is comprised of tissue which acts as a supplier of energy to the muscle or is related to muscle innervation.

To recap all of the above, we can say that there are two methods to gain muscle mass:

The first method is to increase the volume of the type of tissue which acts as an energy supplier to the muscle being exercised, a process known as sarcoplasmic hypertrophy.

The second method is to increase the volume of the contractile tissue, a process known as Myofibrillar pypertrophy.

Let’s analyze both methods in depth:

What’s sarcoplasmic hypertrophy?

Sarcoplasmic hypertrophy is about increasing the volume of the type of tissue which supplies energy to the muscle that’s being exercised. There are tiny organelles within the cells called mitochondria which are the cell’s “energy factories” and produce ATP, the cell’s main energy source. Muscles have fibers which adapt to a high volume of repetitions which are a core part of a standard training regimen, by which the number of mitochondria inside the blood cells increases.

The high number or reps will also cause the increase of the volume of enzymes which are involved in the oxidative phosphorylation and anaerobic glycolysis mechanisms which help with energy production and increase the amount of sarcoplasmic fluid which is found inside the cells, as well as the fluid that is situated between the cells. This hypertrophy type has a negligible on muscle strength and it is mostly related to increased endurance, or the ability to do a certain number of reps with a certain weight and increase the production of ATP inside the muscle.

The Hypertrophy Factor

Sarcoplasmic hypertrophy has the main role in moderate muscle size increases. ATP is the energy source sued in muscle contractions including the contraction of type II muscle fibers. This, logically begs the question: shouldn’t increased sarcoplasmic hypertrophy inside the muscle tissue, which would normally allow an improved ability to increase intramuscular tissue, be a great asset? The answer is most definitely yes.

This is why sarcoplasmic hypertrophy is so important in bodybuilding. And concerning the tissue which is involved with the neural drive, this would theoretically occur in a direct response for the requirement of contracting the cells via the hypertrophied contractile mechanisms. If it were isolated, this wouldn’t provide a great contribution towards increasing muscle size.

Plus, there are many other intracellular bodies whose development and growth would be categorized as sarcoplasmic hypertrophy. Among them are ribosomes whose role in the cells is related to the synthesis of protein. They have a small effect on muscle size, but they aid with the myofibrillar hypertrophy which will be covered in part II.